ST. JOSEPH, La. — A man who believed a device had been implanted in his head shot two hostages, killing one, at a rural Louisiana bank before State Police ended the hours-long standoff by shooting him dead.

The standoff began around 12:30 p.m. Tuesday when authorities said 20-year-old Fuaed Abdo Ahmed took two women and a man captive at a bank.

Charla Ducote, spokeswoman for Rapides Regional Medical Center in Alexandria, La., said the wounded hostage, LaDean McDaniel, was in critical condition Wednesday morning. She could not provide further details.

Several acquaintances said they saw no signs of trouble with Ahmed before the shooting. St. Joseph Mayor Edward Brown said he exchanged pleasantries with Ahmed about an hour before the standoff began. Brown described Ahmed as ‘‘just normal. That’s why it’s so bizarre to me.’’

His high school football coach and a teammate describe an amicable star running back with good grades.